In order to provide for a more comprehensive method of improvement, promotion and development of agricultural research at the Delta Branch Experiment Station, the tax collector of each county of the State of Mississippi located in whole or in part in a levee district, shall deduct annually from all state ad valorem taxes collected by him a sum equal to the avails of a levy of one mill on the dollar of the assessed valuation of taxable property within such county upon which state ad valorem taxes are levied and collected, provided that such county in its discretion levies the one-fourth mill provided for in the third paragraph of this section. Said tax collector is hereby authorized and directed to pay same to Mississippi State University of Agriculture and Applied Science.

Any funds so paid to said university shall be used for agricultural research at the Delta Branch Experiment Station, with primary attention being given to a cotton research program and for providing needed laboratories and other facilities and equipment for agricultural research.

The board of supervisors of any county coming within the provisions of this section shall be authorized to levy, at the time and in the manner other county tax levies are made, and such levy shall be made as a condition precedent to the operation of this section in such county, an ad valorem tax of one-fourth mill against all of the taxable property of such county. Said ad valorem tax levy shall be collected as other taxes are collected, and shall be paid into a special fund of such county and shall be paid over to the Mississippi State University of Agriculture and Applied Science and shall be used at the Delta Branch Experiment Station for agricultural research, with primary attention being given to a cotton research program and for providing laboratories and other facilities and equipment for agricultural research. Such tax levy shall be in addition to all other levies now authorized by law, and no limitation or inhibition now in the statute against the levying of such a tax shall be effective against such levy. Such one-fourth mill ad valorem levies shall not be reimbursed under the Mississippi homestead exemption laws.

In the event similar diversions are already made from the avails of the state ad valorem tax levy in such a county, then this section shall be considered as supplemental thereto, and such laws authorizing such diversions shall not apply to the provisions of this section.